Alarm clock



Feb. 13, 1923.

J. S. HARTLEY.

ALARM CLOCK.

FILED JAN. 20, 1916.

xii WW7 MMMMMU 2mm (111' MAUd Patented Feb. 13, 1923.

UNITED STATES PATENT OFFICE.

JOHN S. HARTLEY, OF LYNN, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO HARTLEY CLOCK COMPANY, OF BOSTON, MASSACHUSETTS.

ALARM CLOCK.

Original application filed January nary 26, 1916.

To all whom it may concern Be it known that 1, JOHN S. HARTLEY, a citizen of the United States, residing at Lynn, in the county of Essex and State of Massachusetts, have invented a new and useful Improvement in Alarm Clocks, of which. the following is a specification.

The present invention relates to alarm clocks.

Alarm clocks are usually provided with a trip lever comprising an arm of spring metal. which is automatically operated to ringthe alarm at a proi'letermined time by a. cam wheel. connected to one of the wheels of the time train, which co-operates with a stationary alarm-set on the setting rod. WVhen the alarm-set drops off a ledge on the cam wheel the alarm is sounded. After the alarm rings for short time a shut-oil. device is manually operated to engage the hammer or some other part of the alarm train for the purpose of silencing the alarm.

, During the continued operation of the -lock the alarm-set travels up a slope on the cam wheel in order to return the alarm-set to a position where it may again drop off the ledge. During its travel up the slope on the cam wheel the alarm-set operates one of the wheels of the time train to overcome the spring tension on the trip lever and thus return it to a position where it again prevents the sounding of the alarm. As well known to those skilled in the art the pressure of the trip lever on the time train during the travel of the alarm-set up the slope on the cam wheel acts as a brake or drag on the time train thus causing the clock to lose time or vary in rate.

The object of the present invention is to relieve the time train of the braking or dragging action of the trip lever and thus improve the time keeping qualities of the alarm clock, but without preventing release of the alarm train by mechanism operating independently of the means actuated. by the time train.

To the accomplishment of this Ubjtll't, and such others as may hereinafter appear, the featuresof the present invention consist in certain devices, combinations and arrangements of parts hereinafter described and.

I then set forth broadly and in detail in the appended claims.

The various features of the present in- 1914, Serial No. 812,687.

Divided and this application filed Jan- Serial No. 73,138.

vention will be best understood from an inspection of the accompanying drawings the preferred embodiment of which, a left side elevation, partly 5: the alarm clock;

sctional elevation on the line and strated embodiment of the inclock is provided with a gong a hollow cylindrical shell casing 2 for the movement c-l- (F l}. The gong is struck tie alarm by a hammer 5 (Fig. fol-riled upon the upper end of an arm whirl: is secured to a rock shaft 7 mount- The (3 is connected by a link 8 to one end lever fl secured to a rock shaft 10 w to rock in the movement plates. 1'

iking movements to the hammer gear ll, actuated in the well .or through a train of gears, called the alarm train. from a g (not shown), cooperating with pallets 12 formed upon the lever 9. 'lhe automatic starting and stopping of the alarm train is controlled by a spring arm 13, called the trip lever, secured at one end to the plate al. As shown in Fig. 3 the "trip lever bent near its attfwhed end so that a pawl 14 formed upon its free end is normally held away from the gear ll. To hold the pawl ll: in engagement with the gear 11 so as to stop the alarm train the trip lever is pressed upon intermediate its ends by a wheel 15 which is driven by the time train from the main spring. The wheel 15 is provided with a cam wheel 16 and is loosely mounted on a setting rod l? which controls-1 the time at which it is desired to ring the alarm. The rod 17 is provided with an, alarm-set l8 (Fig. which travels over the cam. wheel 16. When the set 18 is in the position shown in Fig. the pawl 14: is interposed between a pair of teeth on the gear 11 thus holding the alarm train from ringing the alarm. The cam wheel 16 is rotated by the time train in the direction of the arrow (Fig. 2) thereby transferring the point of engagement of n reina ct iled some clocks and twelve hours in others for the alarm-set to travel up the incline and as the alarm spring is usually exhausted before the alarmhas rung five minutes it is customary to provide alarm clocks with a shut-off device so that the alarm may be silenced before the exhaustionot' the alarm spring. Usually these shut-oft devices engage the hammer to stop the alarn'x. With this construction the alarm-set 18 during its travel up the incline 20 operates the wheel 15 ofthe time train to return the trip lever, against the spring tension thereot to a position Where the pawl thereon extends be tween the teeth of the alarm gear 11. These prior art constructions therefore caused the spring trip lever to act as a bralre or drag on the time train during the travel of the alarm-set 18 up the incline 20. This braking or dragging action on the time train obviously causes the clock to lose time or vary its rate during the tourhour, or more. travel of the alarm-set 18 up the incline 20.

In order to relieve the time train from the braking or dragging action of the spring trip lever the illustrated embodiment of the invention is provided with a pivoted plate 22 arranged to engage the trip lever be tween the Wheel 15 and the secured end of the lever. One end of the plate 22 is beveled as at 23 (Fig. 3) in order that it u'lay ride over the trip lever, when turned from the dotted line position to the full line position (Fig. 2), and wedge it away from the wheel 15 and into engagement with the gear 11. The other end of the plate 22 is biturcated to receive a manually operated shut-off device mounted to slide on the casing 2.

lVith this construction the tension of the trip lever is withdrawn from the wheel 15 during the travel of the alarm-set 18 up the slope 20 on the cam wheel thus relieving the time train ofthe brake or drag to be found in the ordinary alarm clock. The free end portion of the trip lever may be freely flexed to release the alarm train by mechanism operable independently of the time train and shut-off lever. This mechanism, in the present instance, is responsive to temperature changes, and will release the trip lever to soundthe alarm when the clock becomes heated to a predetermined degree.

This mechanism comprises a plunger 28 bracket 88 carried by the casing-"2.

mounted'to slide longitudinally in a yoked bracket 29 secured to the back plate "of the clock works. The plunger 28 is provided with a conical end the point of which is arranged to engagea pinSO, (Figs. 2 and 3), formed on the free end of the trip lever 13. When the plunger is moved forwardly its end strikes the pin 30 and removes the pawl 14: from engagement with the teeth of the gear 11 thus starting the driving mechanism to sound the alarm. The pawl 14- is actuated to release the driving mechanism under the influence of. the plunger'28 even when the plate 22 has been actuated to stop the time controlled movement of the alarm mechanism as thetrip lever is suliiciently flexible between its tree end and the. point of engagementotthe plate 22to permitjthe movement of the pawl 14; away frointhe gear 11.

The plunger 28 is normally held in an in operative position by a coiled spring 31 coiled aroundthe shank oi the plunger and interposed between the bracket29anda block 82 on the rear end of the plunger. The

plunger is actuated forwardly to'wit-hdraw the latch 1 1 by a thermostat comprising a pair of hollow connected disks 38, tilled with ether, which are secured, with fiber washer 3 1 interposed between the disks and theback wall of'the gong 1, by a bolt and nut con nection 35 inside the gong. The outside disk 33 presses against a screw 36 which is ad justably held in thevertical arm of a bell crank lever '37 'pivotally mounted on a I The horizontal arm of the bell crank lever carries a point 39 which engages a cup e0 formed in the block 32. With this construetion an expansion of the ether-filial disks to a predetermined degree actuates, through the connections described. the phurger 28't0 sound analar'm.

The drawings illustrate other novel t'ew tures in alarm clocks, but these features "are not described herein as they aredisclosed in Patent No, 1,200,103, dated October 3, 1916, of which this application is a division.

It will be clear to those skilled in this class of clocks, having" the general objects of the present invention in view, that changes may be made in the details of structure, the de scribed and'illustrated embodiment thereof being intended as anexploitation of its underlying essentials, tliefeatures. thereof being definitely stated'in their true scope in the claims herewith. What is claimed as new is 1. A clock, "having, in combination, an

alarm train, a time train, a trip leversecured at one end to one ot'themovement plates normallyarranged totend to periiiit the operation of the alarm tralinand'to press against one of the wheels of the time train,

and a shut-oil device'for disengaging the trip lever from the wheel of the time train and positioning the trip lever to stop the alarm train arranged to engage the trip lever between its secured end and the wheel or the time train, substantially as described.

2'. A clock, having, in combination, an alarm train, a time train, a trip lever secured at one end to one of the movement plates normally arranged to tend to permit the operation of the alarm train and to press against one or the wheels or the time train, and means for disengaging the trip lever from the wheel of the time train and for locking the trip lever in position to stop the alarm train arranged to engage the trip lever between its secured end and a wheel of the time train, substantially described.

A clock, having, in combination, an alarm train, a time train, a spring metal arm secured at one end to one of the movement plates and normally arranged to press against one of the wheels of the time train, mechanism co-operating with the time train for holding the arm in position to stop the :ilarn': train and for releasing the arm from its alarm train stopping position, and means for relieving the Wheel of the time train from the braking action of the arm when the alarm is silenced arranged to engage the arm between its secured end and the wheel of the time train, substantially as described.

4. A clock, having, in combination, an alarm mechanism, a driving mechanism therefor, a spring metal arm secured at one end to one of the movement plates and normally disposed to tend to permit the operation of the driving mechanism, means for holding the free end of the arm in position to stop the driving mechanism, a timing mechanism co-operating with said means for releasing the arm to start the driving mechanism, and a pivoted plate having one end arranged to engage the arm between its secured end and the point of engagement of said means for locking the arm to prevent its release by the timing mechanism, substantially as described.

5. A clock, having, in combination, an alarm mechanism, a driving mechanism therefor, a spring meta-l arm secured at one end to one of the movement plates and normally disposed to tend to permit the operation or the driving mechanism, means for holding the free end of the arm in position to stop the driving mechanism, a timing lliBCliklIllSIil co-operating with said means for releasing the arm to start the driving mechanism, and a pivoted plate having one end arranged to engage the arm between its secured end and the point of engagement of said means for locking the arm to prevent its release by the timing mechanism and having its other end operatively connected to a manually operated device, substantially as described.

A clock, having, in combination, an alarm train, a trip lever for the alarm train comprising a spring metal arm secured at one end to one otthe movement plates and having its free end positioned for engagement with the alarm train, a time train having one of its wheels arranged to engage the trip lever intermediate its ends. and a shut-off device arranged to engage the trip lever between its secured end and the wheel of the time train, the trip lever between its free end and the wheel of the time train having freedom to flex out of engagement with the alarm train when the shut-off device is in shut-ofl' position, substantially as described.

JOHN S. HARTLEY. 

